Daylight developing tank for roll film having paper protective strips



Oct. 26, 1954 E JAK 2,692,541

M. L S DAYLIGHT DEVELOPING TANK FOR ROLL FILM HAVING PAPER PROTECTIVE STRIPS Filed Nov. 26, 1951 2 Sheets-Sheet l INVENTORQ MICHAEL LESJAK,DECEA5ED, B BABETTE v. LESJAK, BY EXECUTRIX ATTORNEYS Oct. 26, 1954 I M LESJAK 2,692,541

DAYLIGHT DEVELORING TANK FOR ROLL FILM HAVING PAPER PROTECTIVE STRIPS Filed Nov. 26, 1951 2 Sheets-Sheet 2 161$ J J0 l4 2 INVENTOR:

MICHAEL LESJAK,DECEASED BY By BABETTE v. LE5JAK,

E UTRIX M A T TORNEXS Patented Oct. 26, 1954 DAYLIGHT DEVELOPING TANK FOR ROLL FILM HAVING PAPER PROTECTIVE STRIPS Michael Lesjak, deceased, late of Goggingen, Germany, by Babette Viktoria Lesjak, executrix, Goggingen, Germany Application November 26, 1951, Serial No. 258,178

Claims priority, application Germany November 25, 1950 8 Claims.

The present invention relates to a daylight developing tank for roll films having paper protective strips, wherein the roll film is placed in a preliminary supply chamber and from there is introduced into an adjacent developing chamher by pulling out the protective paper strip. More particularly, it concerns means whereby the leading end of the film will become automatically affixed to the take-up axle in the developing chamber.

Daylight developing tanks have long been known. A very successful form is described in the U. S. Patent No. 2,082,962, issued to Lesjak turning of the axle, is pressed against it automatically by suitable means, such as a bowed rod, also on the axle. Said rod may have a projecting end which, when the film clamping device is in open position and the axle is turned in a counterclockwise direction, strikes against a part of the developing chamber, thereby automatically reversing the position of the bow. The film attaching means on the take-up axle may, however, if desired, also be closed manually from outside of the tank. Conveniently, the projecting end of the rod also extends to strike another projection of the developing chamber, thus, preet a1. However, in this known apparatus, it was venting the winding of the film in the wrong necessary, in order to introduce the film edges d rect on, 1. e. Clockwise, at the beginning of the into the spiral grooves in the opposed flanges on winding procedure. For it is essential that the the take-up axle, to press the edges of the film take-up axle be first turned in a counterclockwise slightly together and to guide it to the inner end direction, so that the swingable sliding support of the spiral by means of a swingable guide. The y drop aside and the film be loosely wound thus narrowed film was pulled between the piralabout the axle with its emulsion side outwards. 1y grooved flanges to the axle with the aid of Th r m y l be pr v d a l mp d a pull-in band and a clamp, vice inside the cover of the tank for holding the The main object of the invention is to dispense trailing nd Of t e fi m- Howe e this is not with the spirally grooved flanges, th means for essential, since the end of the film is firmly atnarrowing the film, and, above all, the pull-in tached to the paper protective strip, so that it band of the known apparatus. It has been found that this can be accomplished if one provides a film attaching means directly upon the take-up axle and means whereby the leading end of the film will automatically be guided to such attaching means and grasped thereby.

According to the invention means are provided in the daylight developing tank that guide the film as it enters the developing chamber upon pulling off the protective paper strip, into an open film attaching means such as a clamp, lo-

oated directly on the take-up axle. The means so provided for conducting the leading end of the film to the film attaching means on the takeup axle consist of a stripping device for unrolling the film in the supply chamber and a sliding support arranged between the supply chamber and the take-up axle. This sliding support is swingably mounted near the upper edge of the partition dividing the supply and developing chambers and projects into the opening of the film attaching means on the take up axle. The sliding support, after the introduction of the film end into the attaching device and upon rotating the take-up axle in a counterclockwise direction, drops aside by its own weight and automatically frees the film winding space within the developing chamber.

The film attaching device upon the take-up axle preferably consists of a single clamp jaw that closes against the axle, and which, upon cannot be drawn into the interior of the develop ing chamber. Such a clamping or holding device is preferably adjustable in various positions and may also serve, while partly open, to assist in guiding the film end to the film attaching means on the take-up axle.

The cover of the daylight developing tank according to the invention is preferably made of two overlapping parts between which the paper protective strip may be pulled out. The passage between the overlapping parts should begin in the neighborhood of the stripping device in the supply chamber which serves to unroll the film.

A preferred embodiment of the invention is illustrated by way of example in the accompanying drawings wherein Fig. 1 is aplan view of a developing tank in accordance with the invention, whose cover has been removed,

Fig. 2 is a vertical section of the developing tank with the cover thereon, as the leading end of the film is being introduced into the film attaching means on the take-up axle,

Fig. 3 is the same View as in Fig. 2, however, showing the apparatus after the film end has been affixed and the winding thereof in a counterclockwise direction has begun, and

Fig. 4 is again the same view as in Figs. 2 and 3, but shortly after the reverse winding of the film, i. e. in clockwise direction, has begun.

The details of the apparatus and its operathe opening between the chambers to the opening between the film clamp jaw and the axle.

2. A daylight developing tank as claimed in claim 1, wherein the take-up axle also bears a means for closing the clamp jaw that is actuated by striking a projection in the developing chamber when the axle is turned in a counterclockwise direction.

3. A daylight developing tank as claimed in claim 2, wherein the means for automatically closing the clamp jam consists of a bowed rod having an end portion that strikes against a projection on the lowermost cover portion when turning the axle in a counterclockwise direction.

4. A developing tank as claimed in claim 2, provided with a film clamping means operable from outside of the tank, that holds the film at the opening between two chambers.

5. A daylight developing tank as claimed in claim 4, wherein the holding means consist of a swingable bowed rod whose bowed portion will bear against the sliding support that is mounted at the partition between the two chambers.

6. A daylight developing tank for roll films having paper protective strips, a roll film supply chamber and adjacent developing chamber within said tank, a partition between said chambers, a light-tight cover for both, an opening in the cover through which the paper protective strip may be pulled, wherein the take-up means within the developing tank include a take-up axle within the developing tank, forming a clamping means for the end of the film, and guiding means for directing and introducing the end of the film from the supply chamber between said clamping means, said guiding means including a stripping device for the film in the supply chamber with projections leading to the developing chamber and a swingable mounted sliding support leading from the top of the partition between the supply and the developing chambers .into the mouth formed by the opened clamping means.

7. A daylight developing tank for roll films having paper protective strips, a roll film supply chamber and adjacent developing chamber within said tank, a partition between said chambers, a light-tight cover for bot an opening in the cover through which the paper protective strip may be pulled, wherein the take-up means within the developing tank include a take-up axle within the developing tank, forming a clamping means for the end of the film, and guiding means for directing and introducing the end of the film from the supply chamber between said clamping means, said guiding means including a stripping device for the film in the supply chamber with projections leading to the developing chamber and a swingable mounted sliding support leading from the top of the partition between the supply and the developing chambers into the mouth formed by the opened clamping means, said sliding support being mounted on an axle in the developing chamber adjacent to the top of the partition between said chamber and the supply chamber, and the other end of the sliding support projects into the mouth of the film opened clamping means of the take-up axle and is supported thereby but released on turning the axle in a counterclockwise direction.

8. A daylight developing tank for roll films having paper protective strips, a roll film supply chamber and adjacent developing chamber within said tank, a partition between said chambers, a light-tight cover for both, an opening in the cover positioned to overlie the said developing chamber and juxtaposed opposite the roll film supply chamber immediately above said partition, and film supporting guide means normally positioned to extend between said chambers for directing the leading end of the film as a planar band from the supply chamber to a film attaching and winding means carried in the developing chamber, said guide means having a protective member stripping means integrally carried therewith and positioned in the path of the film as it unwinds from the roll film supply chamber including structure for directing said protective paper to said opening in the cover while the film is being wound up on the film attaching and winding means.

Name Date Freeman Oct. 11, 1949 Numb er 

